This too:
http://www.skbcases.com/industrial/p...s#.YLpBQ5MzbOQ
Ive toured for years and years with this carry on:
https://www.scaliagroup.net/rimowa-s...tte-black.html
And I have almost never had to gate check it.
You can also tell the gate agent you have fragile audio gear and they will usually make sure you can get it on.